I heard that hummingbirds die if you stop them from flapping their wings.

The hummingbird has weak legs so it can't walk or hop like other birds.

At night, Hummingbirds enter a state called torpor.Most of their body energy can be saved by this.

They perch all the time to rest and feed.They sleep all night and sometimes sit on a nest as well.They don't sleep with flapping wings.You wouldn't have had to ask if you thought about his logic.

I've seen them perch, but only for a short time.I think they flap their wings fast to keep their heart rate up.

Hummingbirds are on the branches with their wings folded.Good as new, they fly away.